Sleep Time Calculator
Find ideal bedtimes or wake times using 90-minute sleep cycles.
The Sleep Time Calculator uses 90-minute sleep cycles to recommend bedtimes or wake times. Enter your target time, choose how quickly you fall asleep, and pick 4, 5 or 6 cycles to see the options.
Mode
Recommended times
- 21:456 cycles
- 23:155 cycles
- 00:454 cycles
How to use
- Choose whether you want to wake up at a time or go to bed at a time.
- Set the time, the number of sleep cycles and how many minutes it takes to fall asleep.
- Compare the recommended times and copy the list.
Frequently asked questions
How long is one sleep cycle?
The calculator uses the common 90-minute sleep cycle estimate.
Can I use a custom fall-asleep time?
Yes, the fall-asleep time can be set from 5 to 60 minutes and is included in every calculation.
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